Transcript for Mystery of Flight 370: Pings Vanish
missing flight. Five weeks ago this weekend vanishing. This evening, something else vanished, too. The pings. While authorities believe the underwater signals were the real thing, they now fear the batteries have likely run out. Tonight, more than two dozen ships and aircraft scouring the region of the Indian ocean for debris. They'll also turn to a new piece of underwater technology. It's a bluefin submersible, a drone they'll send to the ocean floor. Does this mean we're looking at months, perhaps longer. I want to bring in John nance. Our expert. No pings since last week. 37 days. Is it believed that the batteries are wiped out? Yes, if not wiped out, so They got four excellent triangulations on the ocean floor. And that's where, when they put this torpedo-like thing in, the bluefin 21, that's where it have start searching, in the middle of that triank lags. You bring up the submersible. It will scan an area the size of Los Angeles. How long can it stay down there? About 16 hour on station. It takes two hours to go down, two to come back. The total time is 20 hours they can work it. They have to have it go very slowly over the central area and kind of work out. Eventually, they'll map everything down there. Only when it gets to the surface do they know if it picked up anything? Yes, this thing does not transmit to the surface. It has to fillically come back up for them to pull the recorder and the chips and all the data they have got. Same thing with the photographic part. John nance with us tonight,
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